Clostridium

a genus of bacterium occurring in soil, water, and the intestinal tracts of humans and lower animals. Some infections caused by these organisms have musculoskeletal effects.

Gas gangrene may occur in wounds that are contaminated by clostridial organisms. These anaerobic microorganisms produce gas and cause extensive tissue destruction. Gas gangrene is characterized by severe pain and an oedematous, pulseless limb. A clostridial cellulitis may also occur.

Radiographically, subcutaneous tissues or muscles may show radiolucent collections of gas, which are linear or netlike in the subcutaneous locations and circular in muscles (Fig.1). Gas collections in soft tissues are not specific for clostridial infections, but may also be seen in some cases of infections with Escherichia coli, other coliform bacteria, streptococci and Bacteroides species.

Septic arthritis may also be produced by clostridia introduced into a joint by contamination from a penetrating injury or by haematogenous spread from the gastrointestinal tract. Usually only a single joint is involved. Joint space narrowing, bone defects and gas collections in the joint or adjacent soft tissues may be observed on radiographs.

DR/RB